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  1. #1
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    Floodgate - please explain...!

    Can someone please explain in simple terms what the Floodgate actually does on a Rock Shox with PopLoc remote?

    I have a vague idea after reading some of the posts, but having come from Fox Shox I'm not 100 per cent sure. Is it the same as the "T" on a set of F80RLTs?

    Dave V.

  2. #2
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    http://www.sram.com/en/pike/
    the motion control has a compression damper with two fixed-size orifices, one larger than the other.
    The size of the little orifice is externally adjustable, up to lockout, with the poplock.
    The large orifice is normally closed down by the "gate".
    The floodgate sets how much millimeters the plastic spring must be compressed to open up the gate.
    The compression of the plastic spring depends on the pressure build up under the gate, and the pressure depends on:
    - rate of the plastic spring
    - compression speed
    - oil viscosity
    Last but not least:
    - size of the little orifice
    So the Floodgate "threshold" is a "lockout threshold" if the Gate is closed, otherwise is a "high speed threshold".

  3. #3
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    this article by angry asian should help a little.

  4. #4
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    Quote Originally Posted by ClaudeFr
    http://www.sram.com/en/pike/
    the motion control has a compression damper with two fixed-size orifices, one larger than the other.
    The size of the little orifice is externally adjustable, up to lockout, with the poplock.
    The large orifice is normally closed down by the "gate".
    The floodgate sets how much millimeters the plastic spring must be compressed to open up the gate.
    The compression of the plastic spring depends on the pressure build up under the gate, and the pressure depends on:
    - rate of the plastic spring
    - compression speed
    - oil viscosity
    Last but not least:
    - size of the little orifice
    So the Floodgate "threshold" is a "lockout threshold" if the Gate is closed, otherwise is a "high speed threshold".
    Cheers ClaudeFr...Very helpful. Much appreciated.

    Dave V.
    Australia

  5. #5
    Dagenham Dave
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    Quote Originally Posted by Cyco-Dude
    this article by angry asian should help a little.
    Yes this article by Angry Asian was very helpful.

    Thanks Cyclo-Dude...

  6. #6
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    Quote Originally Posted by Dave V.
    Yes this article by Angry Asian was very helpful.

    Thanks Cyclo-Dude...
    I am sorry but that doesnt seem to work that way.
    I read in an article that that only works in the boxxer fork, I cant recall if that worked for the Pike or not, but that in the case of the Reba the Floodgate created a platform effect, and it reulated the ammount of force needed for the fork to break into its regular travel.

    You will notice this very easily in the REBA.
    If you crank the compression you will not get the brake dive and/or anti bob, your fork will move but it will be require more force to o throug its travel.
    If you mess with the floodgate then what you get is a platform effect.
    Turn the floodgate all the wayand your fork wont move at all, unless you are over 300 pounds. Turn the floodgate all the way off and even if you have the compression in the locked position yur fork will use all of its travel. Unless of course you weight 100 pounds.

    So:
    Compression locked-floodgate all the way counterclockwise: the fork reacts to most bumps it is almost completely active with some bobbing and brake dive but only in its initial travel; it has more resistance to bottoming out.
    Compression locked- floodgate all the way clockwise: The fork doenst move at all, Nada.
    Compression unlocked-floodgate all the way couterclockwise:the fork reacts to any sized bumps it is completely active with bobbing and brake dive. PLUSHEST SETTING
    Compression unlocked floodgate all the way clockwise: There is no platform feeling, you require the compression to be more than half way to the locked position to experience it.
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  7. #7
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    Quote Originally Posted by Cyco-Dude
    this article by angry asian should help a little.
    That was a good article, though I don't think the second setup.......

    Low-speed compression damping relatively open for excellent small-bump sensitivity, but firm Floodgate for resistance to bottoming on really big stuff.

    works too well that way, unless you consider "spiking" to be resistance to bottoming.

  8. #8
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    Quote Originally Posted by kapusta
    That was a good article, though I don't think the second setup.......

    Low-speed compression damping relatively open for excellent small-bump sensitivity, but firm Floodgate for resistance to bottoming on really big stuff.

    works too well that way, unless you consider "spiking" to be resistance to bottoming.
    hmm...i have more testing to do, but it seems that wouldn't work too well. for me, when i have the compression full open and start to turn the floodgate to a firmer setting, the small-bump plushness disappears fast, and you need a bigger hit to activate the fork. in that sense it does provide resistance to bottoming on big hits.

    i don't know how much time he had on the pike and reba befor writing this (i believe this was posted on his website over a year ago?). he could probably give a much better description of how it works today. see if there's anything on his forums; i don't have flash installed otherwise i'd look myself.

  9. #9
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    I find that the floodgate does nothing unless you have upped the compression. And after doing some reading at the RockShox site i think floodgate will only work if compression is increased from full open. Have not tried this mayself yet, but plan on it soon.
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  10. #10
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    Quote Originally Posted by kirbster1966
    I find that the floodgate does nothing unless you have upped the compression. And after doing some reading at the RockShox site i think floodgate will only work if compression is increased from full open. Have not tried this mayself yet, but plan on it soon.
    Quote Originally Posted by Cyco-Dude
    hmm...i have more testing to do, but it seems that wouldn't work too well. for me, when i have the compression full open and start to turn the floodgate to a firmer setting, the small-bump plushness disappears fast, and you need a bigger hit to activate the fork. in that sense it does provide resistance to bottoming on big hits.

    i don't know how much time he had on the pike and reba befor writing this (i believe this was posted on his website over a year ago?). he could probably give a much better description of how it works today. see if there's anything on his forums; i don't have flash installed otherwise i'd look myself.

    Thats exactly what i explained above
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  11. #11
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    Quote Originally Posted by kapusta
    That was a good article, though I don't think the second setup.......

    Low-speed compression damping relatively open for excellent small-bump sensitivity, but firm Floodgate for resistance to bottoming on really big stuff.

    works too well that way, unless you consider "spiking" to be resistance to bottoming.
    I run floodgate about 3/4 closed and compression about 1/2 to 3/4 way. 1/2 way results in a very plush and active initial stroke, but becomes more progressive towards the end stroke, however, it still maintains a very smooth feeling. At 3/4 way it feels more like it's spiking. The travel becomes much harsher, but it's still moving.

    The Pike is a little linear, but I have never bottomed mine. I run the maximum oil height. I want to switch to the firm springs though.

  12. #12
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    Quote Originally Posted by Cyco-Dude
    for me, when i have the compression full open and start to turn the floodgate to a firmer setting, the small-bump plushness disappears fast, and you need a bigger hit to activate the fork.
    i'll go ahead and modify my previous comment: with compression full open and floodgate set firm, the fork is compliant on small or low-speed impacts, such as coasting slowly off of a curb.

    what i was doing befor was testing the floodgate setting while riding fast down some stairs (about 5-6 inches tall and maybe three feet long). the fork was harsh with the floodgate set firm (four full turns in or 32 clicks). but coasting down slowly was more compliant.

    i haven't spent enough time tinkering with air pressures or compression yet (besides locked out). as it is i have the floodgate set just firm enough to resist bobbing when i'm locked out and hammering out of the saddle, which seems to be about 24 clicks from full open (or three full turns).


    what was the question again???

  13. #13
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    Quote Originally Posted by Dave V.
    Can someone please explain in simple terms what the Floodgate actually does on a Rock Shox with PopLoc remote?

    I have a vague idea after reading some of the posts, but having come from Fox Shox I'm not 100 per cent sure. Is it the same as the "T" on a set of F80RLTs?

    Dave V.
    I am seeing some posts claiming that the floodgate can be set up to resist bottoming. Perhaps I am misunderstanding them, but the floodgate does NOT help resist bottoming. All the floodgate can do is BYPASS (turn off) the compression circut. Whatever you have the compression dial set to is the maximum compression dampening you are going to get. Setting the floodgate fully firm simply means it is NOT going to bypass the compression damper. and what you have left is a simple "unshimmed" damper with no high speed blow off. It is not progressive in the sense of being possition sensitive (it does not ramp up at the end of the stroke) but it does "spike" at higher shaft speeds, thus feeling harsh. I guess you could call that "bottoming resistance", but that is not what the term generally refers to.

    The floodgate opens up when a certain amount of pressure builds up at the compression damper. The floodgate adjustment adjusts how much pressure (or resistance) is required to do so. A firm (clockwise) setting means that it requires a lot of pressure to open the floodgate. Two things increase the pressure at the damper: The size of the damper hole (which is what the compression adjustment changes) and the speed of the fluid pushing through it. Smaller hole (which is a high, clockwise compression dampening setting) and faster moving fluid (faster moving shaft) means more pressure. So here is how this can play out in 4 different scenarios:

    1) With the compression all the way open (lowest or counterclockwise setting) the floodgate setting makes little difference because the fluid (and therefore the fork shaft) have to move incredibly fast to build up enough pressure to open the floodgate. The floodgate must be set to full soft (counter clockwise, lowering the pressure needed to override the compression damper) in order to have any effect. So what you have is very little compression dampening until you have a big, fast hit, and then you have even less. Personally, I don't see why anyone would want this (compression and floodgate both at min). You'd may as well just loose the compression damper and the floodgate altogether, and save some weight and money. Plus, as I will explain below, the lockout feature is also now totally useless.

    2) With a more moderate compression setting, with the Floodgate set to open at higher fork (an fluid) speed you have something like Marzocchi's HSCV that overrides the damper just as it reaches the fluid speed that causes spiking. I used this setting for a while and it felt a lot like my `03 Z1 FR.

    3) With a high compression setting (small damper hole), pressure builds up very easily at lower fluid speeds. The floodgate is set up to open at pretty low fuid speeds. This gives you a fork that resists bobbing and diving fairly well, but opens seamlessly up for any bumps. This is my favorite setup.

    4) When you "lock out" the fork you are essentially closing the compression damper, so no fluid gets through. Any force the shock experiences will translate to pressure at the compression damper. This is where the setting of the floodgate is most noticable. Full firm setting means the shock is going to be very difficult to move. It is truely locked out. As you lighten it up though, the compression damper is easier to override and the fork can be set to feel locked out, but it will react to larger hits. As you get to the really light settings, the fork has more of a "platform" feel to it. However, I don't think it is accurate to say it's like most platform shocks. Once the floodgate is open you have no control over the compression dampening characteristics. Most platform shocks that I am familiar with have some well though out compression dampening circuts that are in effect even after the platform is breached. For example, Manitou SPV shocks have a compression circut that ramps up at the end of the stroke to resist bottoming, and often you can adjust how much it ramps up.

    The trick thing about the floodgate setting is that it has a different result when your fork is locked and unlocked. The compression/floodgate setting that works well in the unlocked position (scenarios #1, 2, 3) may not have the floodgate setting you want when you lock the fork (scenario #4, if you ever do that). For example, for my unlocked setting I run high compression with a very light floodgate setting (scenario 3). I think this is the best feel for me. However, this means that when I use the lockout, the floodgate opens up more easily than I would like. It's not a lockout at all. However, I do notice a little more resistance to movement, and it can be a useful feature when going down something REALLY steep, and it helps me launch drops and jumps more easily. I use it less and less, however, and I am considering trying to ditch the poplock altogether. For people using #1 and #2, however, the locked out setting (#4) will perform much more like a lockout.

    Does this answer your question?

  14. #14
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    Very nice post kapusta. That's the best explaination that I've heard yet.
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    Quote Originally Posted by kapusta

    4) When you "lock out" the fork you are essentially closing the compression damper, so no fluid gets through. Any force the shock experiences will translate to pressure at the compression damper. This is where the setting of the floodgate is most noticable. Full firm setting means the shock is going to be very difficult to move. It is truely locked out. As you lighten it up though, the compression damper is easier to override and the fork can be set to feel locked out, but it will react to larger hits. As you get to the really light settings, the fork has more of a "platform" feel to it. However, I don't think it is accurate to say it's like most platform shocks. Once the floodgate is open you have no control over the compression dampening characteristics. Most platform shocks that I am familiar with have some well though out compression dampening circuts that are in effect even after the platform is breached. For example, Manitou SPV shocks have a compression circut that ramps up at the end of the stroke to resist bottoming, and often you can adjust how much it ramps up.
    I think you are slightly off there. The floodgate isn't an on/off switch. It does in fact provide damping through the whole stroke when lockout has been breached.

    The thing that makes it feel good for trail riding is the fact that the floodgate pressure release is actually linear. Just about every other high end fork is progressive. The linear feel of the floodgate release makes for a plush trail fork, but does not ramp up quite like others. This still doesn't mean there isn't damping through the whole stroke, it takes pressure to keep the floodgate open.

    The motion control in the boxxers has an added shim stack to make the floodgate more progressive in damping, which is the inherent trait of shims.


    ON top of all this, the motion control damper is IN FACT A PROGRESSIVE UNIT. It has a small air chamber in the swiss cheese unit that get compressed to nearly full capacity. Just the slightest amount of being low on oil in the damper can reduce its progression. If you remove the spring from the fork and compress the fork, you will see that the damper ramps up the spring rate quite a bit in the last 1 inch.

  16. #16
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    Quote Originally Posted by SpawningGround
    I think you are slightly off there. The floodgate isn't an on/off switch. It does in fact provide damping through the whole stroke when lockout has been breached.

    The thing that makes it feel good for trail riding is the fact that the floodgate pressure release is actually linear. Just about every other high end fork is progressive. The linear feel of the floodgate release makes for a plush trail fork, but does not ramp up quite like others. This still doesn't mean there isn't damping through the whole stroke, it takes pressure to keep the floodgate open.

    The motion control in the boxxers has an added shim stack to make the floodgate more progressive in damping, which is the inherent trait of shims.


    ON top of all this, the motion control damper is IN FACT A PROGRESSIVE UNIT. It has a small air chamber in the swiss cheese unit that get compressed to nearly full capacity. Just the slightest amount of being low on oil in the damper can reduce its progression. If you remove the spring from the fork and compress the fork, you will see that the damper ramps up the spring rate quite a bit in the last 1 inch.
    First, I was talking about the motion control on the Pike and Reba. I don't know much about the Boxxer. If the boxxer has a shim stack beyond the floodgate, then what I am saying would not really apply. But as for the Reba and Pike:

    I did not say it was an on-off switch, I said it bypasses the main compression circut. Sure, is still has some compression damping going on, but my point still stands (whether that constitutes an on-off switch is an open question). Once the floodgate opens, you just have a larger hole that the fluid is going through. I'm not saying that is a bad thing. That's all HSCV, (or any shimmed damper) comes down to. The point I made that I believe you are refering to is that when the floodgate is combined with a locked out compression to achieve a platform effect, you loose any control beyond the point of the floodgate opening. On the Reba and Pike there is no compression adjustment for when the floodgate is open. You don't really have the ability to fine tune it. Many SPV type forks and shocks have compression adjustments beyond when the platform is breached, and most offer a way to make the compression dampening progressive. The motion control on the Pike and Reba do not offer this. It's not a big deal, as in most of the scenarios I described it is un-necessary.

    I have heard conflicting accounts on whether the Pike uses a trapped air bubble to help prevent bottoming and I have not played around with oil levels myself, but either way, an air bubble is NOT the same as progressive dampening. You are increasing the SPRING RATE in the last part of the travel, not the compression dampening. I don't think it really has anything to do with the motion control dampening system. It's a bottom out bumper that uses air instead of rubber. Perhaps we are splitting hairs if we argue about whether this is part of the motion control damper. It is in the motion control unit, but it is not a damper, and it is not adjustable (unless you change the oil level). It does not become firmer with heavier compression and floodgate settings.

  17. #17
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    Quote Originally Posted by kapusta
    1) With the compression all the way open (lowest or counterclockwise setting) the floodgate setting makes little difference because the fluid (and therefore the fork shaft) have to move incredibly fast to build up enough pressure to open the floodgate. The floodgate must be set to full soft (counter clockwise, lowering the pressure needed to override the compression damper) in order to have any effect.
    Do you guess that, or have you experienced such feeling? Could it be true for a heavy rider but not for a light rider?

    I like my Reba with full open Compression setting, but haven't tried many different Floodgate settings with that Compression setting. The Floodgate is in the middle now. Nice swallowing of obstacles, no really bad diving or "bobbing", though I don't stand and pedal much, and no bad bottom-outs.

    I think that if you really seriously want to grade different, absolute compression damping settings, low and high speed, and say that one is better feeling than the other, then you also need to consider the chosen spring rate and the rider's weight.

    The fork's travel over a bump is affected by both spring and damping characteristics. Over one specific shape of bump, you should be able to get the exact same feeling with a softer spring with more compression damping and less rebound damping, as with a stiffer spring with less compression damping and more rebound damping. When then going over other shapes of bumps, the two settings will feel different with one compressing less over some bumps and the other less over others. For example, a deep and gradual bump would compress the setting with a softer spring more, while a square-edge rock would compress the one with a stiffer spring more.

    Maybe I like little compression damping because I am on the light side myself and happen to have a spring rate on the stiff side for my weight? I don't know, but I am sure I would like more compression damping if I would choose a softer spring rate. Would it ride better for me and my bumps? I don't know yet :-)

  18. #18
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    Quote Originally Posted by anden
    Do you guess that, or have you experienced such feeling? Could it be true for a heavy rider but not for a light rider?

    I like my Reba with full open Compression setting, but haven't tried many different Floodgate settings with that Compression setting. The Floodgate is in the middle now. Nice swallowing of obstacles, no really bad diving or "bobbing", though I don't stand and pedal much, and no bad bottom-outs.

    I think that if you really seriously want to grade different, absolute compression damping settings, low and high speed, and say that one is better feeling than the other, then you also need to consider the chosen spring rate and the rider's weight.

    The fork's travel over a bump is affected by both spring and damping characteristics. Over one specific shape of bump, you should be able to get the exact same feeling with a softer spring with more compression damping and less rebound damping, as with a stiffer spring with less compression damping and more rebound damping. When then going over other shapes of bumps, the two settings will feel different with one compressing less over some bumps and the other less over others. For example, a deep and gradual bump would compress the setting with a softer spring more, while a square-edge rock would compress the one with a stiffer spring more.

    Maybe I like little compression damping because I am on the light side myself and happen to have a spring rate on the stiff side for my weight? I don't know, but I am sure I would like more compression damping if I would choose a softer spring rate. Would it ride better for me and my bumps? I don't know yet :-)
    Well, I would not have called it a "guess", but yes, I have noticed that as the amount of compression dampening is reduced the efffect of the floodgate is less dramatic. I was in fact guessing that the floodgate would have to be set a FULL soft to kick in. I should have said VERY soft.

    I'm not saying which settings are better, I'm just explaining how it works. I just mentioned that I like heavy compression with a light floodgate, others may like something else entirely. That's the great thing about the fork. Certainly if you are a light person with a stiffer spring you would want less compression dampening than a heavy person on a light spring.

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    Quote Originally Posted by kapusta
    That was a good article, though I don't think the second setup.......

    Low-speed compression damping relatively open for excellent small-bump sensitivity, but firm Floodgate for resistance to bottoming on really big stuff.

    works too well that way, unless you consider "spiking" to be resistance to bottoming.

    actually, a stronger ramping up of the damping gives a much more controlled, positive feel on large huck landings and keeps the fork from blowing through the travel too quickly and jarring the rider. I'm not sure if "spiking" is the best term, but it's what you'd want. Fast DH chatter bumps are where you would want floodgate wide open, similar to hscv marzocchi damping. It's all personal preference, but I like more high speed compression for jumping, less for DH. I think the article is spot on.

  20. #20
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    Nit-Picking - irrelevant ultimately, but could you all stop say DAMPENING - that means to moisten, or prepare an ink transfer; what we are discussing is called DAMPING.

    that is all.

  21. #21
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    Quote Originally Posted by Huck Banzai
    Nit-Picking - irrelevant ultimately, but could you all stop say DAMPENING - that means to moisten, or prepare an ink transfer; what we are discussing is called DAMPING.

    that is all.
    the dictionary has more than one definition for that word. dampening is the correct term to use here. "damping" is incorrect english.

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    Quote Originally Posted by Huck Banzai
    Nit-Picking - irrelevant ultimately, but could you all stop say DAMPENING - that means to moisten, or prepare an ink transfer; what we are discussing is called DAMPING.

    that is all.
    Dampening is completely correct to use in this fashion. Both terms are correct.

  23. #23
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    Quote Originally Posted by kapusta
    Dampening is completely correct to use in this fashion. Both terms are correct.
    Yes, Kapusta is correct.

    And if you go back in history the "moistening" meaning is connected to the hydraulic meaning. You can damp a fire (lessen its intensity) by shutting down the air flow or by putting damp wood on it. That's how the two meanings are connected.

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    actually, a stronger ramping up of the damping gives a much more controlled, positive feel on large huck landings and keeps the fork from blowing through the travel too quickly and jarring the rider. I'm not sure if "spiking" is the best term, but it's what you'd want.

    I think I agree with you. The point I was making is that when you have a firm enough floodgate setting combined with a light enough compression setting, the floodgate might not even open. When the floodgate does not open then you essentially have an unshimmed damper. Sure, you can run a light compression setting and the resistance will ramp up significantly with higher speed impacts, and you are correct that this is fine for drops. This is why many dirt jumping forks can use relatively simple compression dampers (SSCV or something like that, I can't remember what Marzocchi calls it). I guess I just don't think of that as a great solution to bottoming. After all, this spiking could happen well before you come close to bottoming your fork because it is speed sensitive and not possition sensitive. A progressive compression damper or a progressive spring rate at the end of the stroke seems like a better solution to me, but I guess for hucks and drops like you are describing it may work fine. Hey, if it works for you, that's great! Plenty of people use and love Marzocchi Dirt Jumper forks.

    Fast DH chatter bumps are where you would want floodgate wide open, similar to hscv marzocchi damping. It's all personal preference, but I like more high speed compression for jumping, less for DH


    I sort of agree here, but I would sat "more open" rather than "wide open". With the floodgate wide open you don't have much of any dampening going on at any compression setting. That's fine if that's what you are looking for.

  25. #25
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    actually, a stronger ramping up of the damping gives a much more controlled, positive feel on large huck landings and keeps the fork from blowing through the travel too quickly and jarring the rider. I'm not sure if "spiking" is the best term, but it's what you'd want.

    I think I agree with you. The point I was making is that when you have a firm enough floodgate setting combined with a light enough compression setting, the floodgate might not even open. When the floodgate does not open then you essentially have an unshimmed damper. Sure, you can run a light compression setting and the resistance will ramp up significantly with higher speed impacts, and you are correct that this is fine for drops. This is why many dirt jumping forks can use relatively simple compression dampers (SSCV or something like that, I can't remember what Marzocchi calls it). I guess I just don't think of that as a great solution to bottoming. After all, this spiking could happen well before you come close to bottoming your fork because it is speed sensitive and not position sensitive. A progressive compression damper or a progressive spring rate at the end of the stroke seems like a better solution to me, but I guess for hucks and drops like you are describing it may work fine. Hey, if it works for you, that's great! Plenty of people use and love Marzocchi Dirt Jumper forks.

    Fast DH chatter bumps are where you would want floodgate wide open, similar to hscv marzocchi damping. It's all personal preference, but I like more high speed compression for jumping, less for DH


    I basically agree here, but to compare it to HSCV I would say "more open" rather than "wide open". With the floodgate wide (full) open you don't have much of any dampening going on at any compression setting. That's fine if that's what you are looking for.

  26. #26
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    Quote Originally Posted by SpawningGround
    ON top of all this, the motion control damper is IN FACT A PROGRESSIVE UNIT. It has a small air chamber in the swiss cheese unit that get compressed to nearly full capacity. Just the slightest amount of being low on oil in the damper can reduce its progression. If you remove the spring from the fork and compress the fork, you will see that the damper ramps up the spring rate quite a bit in the last 1 inch.
    I don't think this is true. When I had the fork apart, I could push in the shaft on the motion control side all the way. With the proper amount of oil, there is no resistance to bottoming from the trapped air volume.

  27. #27
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    Quite a lot of Motion Control units have a broken o-ring or tend to leak oil/air, right under the compression knob. This results in low bottoming resistance and you can push the MC side all the way in. Check if your MC side is leaking air!

    I love my Pike.

  28. #28
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    Quote Originally Posted by kapusta
    3) With a high compression setting (small damper hole), pressure builds up very easily at lower fluid speeds. The floodgate is set up to open at pretty low fuid speeds. This gives you a fork that resists bobbing and diving fairly well, but opens seamlessly up for any bumps. This is my favorite setup.
    First off, very useful post, thank you!

    I run a custom Totem coil with a speedstack motion control damper inside(the one that came on the Demo 7 -07s) The tip above is what I want. Im guessing that with your settings and the addition of the internal boxxer high speed shim stack, I should be able to achieve what you say, but with added bottom out/high speed control towards the end of the stroke..?

    Anyone try this, or try to tune this damper?

    Thanks
    Fredrik
    Swedish trail/AM/Enduro/DH-rider - Currently rides Spitfire V2 & Devinci Wilson SL. Spending the summer 2013 in Whistler, BC.

  29. #29
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    Hi guys, I'm considering going back to a coil Pike. I never could figure out how to set it up correctly before (i.e. I didnt give it enough time). For fast, technical/rocky terrain- would would you recommend to stop the fork being overwhelmed/packing up?

    Floodgate set to almost off- rebound two clicks off full fast and compression dial just off fully anti-clockwise?

  30. #30
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    Quote Originally Posted by beanbag
    I don't think this is true. When I had the fork apart, I could push in the shaft on the motion control side all the way. With the proper amount of oil, there is no resistance to bottoming from the trapped air volume.
    Hello, what weight oil and cc should be put into which leg (Uturn dial or compression side?). How much different is it from the stock oil level?

    I've been looking for the perfect stiff fork for a while- I think I should reinvestigate the Pike properly this time....

  31. #31
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    Hell, I never realised the floodgate had such an effect on the compression when turned "off", thanks for the info. I always thought the floodgate was only to firm the fork up with a simple turn to assist climbing and to be adjustable for bumps when engaged. I sold my Pike a while ago and been riding a Domain, considering going back to a Pike for weight but still hesitating. I found the Pike coudnt handle big hits and I kept blowing the lip seal. I was on a firm spring at 180lbs and even tried the Xfirm which was too much for bumpier trails. Understanding the floodgate may help.
    I am also on a Totem and not convinced it is riding in the sweet spot and now I think I need to play more with the floodgate. Riders have been removing the floodgate on the Totem to help improve small bump sensitivity and bottom out. I would prefer to keep it in for Climbing but if I dont get things right by changing the settings I may whip it out. There isnt a good contender for the Pike so I may have to give it one more go.

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    Quote Originally Posted by claycooper
    Fast DH chatter bumps are where you would want floodgate wide open, similar to hscv marzocchi damping. It's all personal preference, but I like more high speed compression for jumping, less for DH. I think the article is spot on.
    This is the setting that I need- just to double check. Floodgate wide open is full anti-clockwise and the compression is set to clockwise or anti-clockwise?

  33. #33
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    Quote Originally Posted by kapusta
    actually, a stronger ramping up of the damping gives a much more controlled, positive feel on large huck landings and keeps the fork from blowing through the travel too quickly and jarring the rider. I'm not sure if "spiking" is the best term, but it's what you'd want.

    I think I agree with you. The point I was making is that when you have a firm enough floodgate setting combined with a light enough compression setting, the floodgate might not even open. When the floodgate does not open then you essentially have an unshimmed damper. Sure, you can run a light compression setting and the resistance will ramp up significantly with higher speed impacts, and you are correct that this is fine for drops. This is why many dirt jumping forks can use relatively simple compression dampers (SSCV or something like that, I can't remember what Marzocchi calls it). I guess I just don't think of that as a great solution to bottoming. After all, this spiking could happen well before you come close to bottoming your fork because it is speed sensitive and not position sensitive. A progressive compression damper or a progressive spring rate at the end of the stroke seems like a better solution to me, but I guess for hucks and drops like you are describing it may work fine. Hey, if it works for you, that's great! Plenty of people use and love Marzocchi Dirt Jumper forks.

    Fast DH chatter bumps are where you would want floodgate wide open, similar to hscv marzocchi damping. It's all personal preference, but I like more high speed compression for jumping, less for DH


    I basically agree here, but to compare it to HSCV I would say "more open" rather than "wide open". With the floodgate wide (full) open you don't have much of any dampening going on at any compression setting. That's fine if that's what you are looking for.
    Since it has been three years since I wrote the above post, I should say that my view towards running the FG wide open has changed. The reason for this change is that I find that different models of the MoCo unit seem to have slightly different FG ranges, so that "full open" on the one I have with the internal FG adjustment feels like 2/3 turn from full open on the external FG adjusted poplock model.

  34. #34
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    Quote Originally Posted by hora
    This is the setting that I need- just to double check. Floodgate wide open is full anti-clockwise and the compression is set to clockwise or anti-clockwise?
    Come on, you really need to be able to figure this one out yourself. With the compression and floodgate both closed, the fork won't move. If either one is in the full open position, you will be able to compress the fork easily. Figure it out.

  35. #35
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    Quote Originally Posted by kapusta
    Since it has been three years since I wrote the above post, I should say that my view towards running the FG wide open has changed. The reason for this change is that I find that different models of the MoCo unit seem to have slightly different FG ranges, so that "full open" on the one I have with the internal FG adjustment feels like 2/3 turn from full open on the external FG adjusted poplock model.
    So, are you saying that the external FG adjust version allows a greater range of FG settings?

    Do you think there is any difference between the poploc and non-poploc carts? Seems like the only difference is the spring return in the poploc version.

  36. #36
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    Quote Originally Posted by derailin_palin
    So, are you saying that the external FG adjust version allows a greater range of FG settings?

    Do you think there is any difference between the poploc and non-poploc carts? Seems like the only difference is the spring return in the poploc version.
    I'm not sure. The external version I have has more turns from full open to full closed, but that does not mean it has a greater range. What I can say is that I run the internal version nearly full open, and ran the external 2/3 from full open.

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    Kay, I have read this thread 3 times and the only thing confusing me now is whether the settings being given are with the Floodgate activated or not. I understand that the FG will have an effect on compression even in "off" setting and only if there is some LSC added, but with all the settings listed there is no real mention that FG is "on" or "off".
    I am probably pulling my FG out of my Totem this week but it would still be nice to know if I could improve the fork with the FG in. I experimented with floodgate in firm setting(fully clockwise) but in "off" position and LSC fully clockwise and while there was some bobbing it felt fine for climbing. Doesnt take much to turn it all the way and while FG is quicker to activate it do me fine if the performance is improved. I have read a huge improvement in overall performance with the FG removed but that is for FR and DH applications.

    Nice thread.

  38. #38
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    Quote Originally Posted by juan pablo
    Kay, I have read this thread 3 times and the only thing confusing me now is whether the settings being given are with the Floodgate activated or not. I understand that the FG will have an effect on compression even in "off" setting and only if there is some LSC added, but with all the settings listed there is no real mention that FG is "on" or "off".
    I am probably pulling my FG out of my Totem this week but it would still be nice to know if I could improve the fork with the FG in. I experimented with floodgate in firm setting(fully clockwise) but in "off" position and LSC fully clockwise and while there was some bobbing it felt fine for climbing. Doesnt take much to turn it all the way and while FG is quicker to activate it do me fine if the performance is improved. I have read a huge improvement in overall performance with the FG removed but that is for FR and DH applications.

    Nice thread.
    First, I don't know that what is described here applies to the totem.

    Second, you don't turn the floodgate "on or off" when you engage the lockout. You turn the COMPRESSION to full close. The floodgate does not change when you do this. So, what you are referring to as the floodgate "on" is described as setting with the compression fully closed.

  39. #39
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    Why wouldnt it apply Dave? Is it cause the Totem has LSC and HSC?

    I see my mistake with the FG and lockout issue. What I am trying to understand is the fact that the lockout feature can be set from full hard to soft when activated, controling bob but allowing the fork to manage bumps at the same time. This is for climbing only. I was under the impression that the FG was the method of setting the firmness of the lockout function(when activated of coarse). I didnt realise the floodgate had an effect on compression when the lockpout was turned off, judging from information here that is what is happening right?

  40. #40
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    Quote Originally Posted by juan pablo
    Why wouldnt it apply Dave? Is it cause the Totem has LSC and HSC?
    Well, I'm not Dave, but I think you were addressing me. All I'm saying is that I know how the MoCo in the Pike/Reba/older Revs pretty well, and feel pretty confident about the way I describe it. However, I think there are more compression adjustments on the Totem, and I don't really know exactly how the FG adjustment interacts with these, so therefore I have no worthwhile advice on the matter.
    I see my mistake with the FG and lockout issue. What I am trying to understand is the fact that the lockout feature can be set from full hard to soft when activated, controling bob but allowing the fork to manage bumps at the same time. This is for climbing only. I was under the impression that the FG was the method of setting the firmness of the lockout function(when activated of coarse). I didnt realise the floodgate had an effect on compression when the lockpout was turned off, judging from information here that is what is happening right?
    If you are talking about a Pike/Reba/Revalation, yes, that is what is happening. FG is the way you set the firmness of the fork with the compression in the "lockout" (fully closed) position. However, it also effects the action of the fork with the compression adjustment in various "unlocked" positions. As I said, there is a bit of compromise in having the FG hard enough to make the lockout useful, and what feels best when the fork is "unlocked". For example, in my Pike, I run the floodgate very light so that it feels very good while running a moderate amount of compression. Due to the light FG setting, the lockout feature is minimally useful at best. If I've tried to run the FG hard enough to make a real difference in the locked-out position, I sacrificed plushness on fast hits.

    Totem? I don't know if any of this applies.

  41. #41
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    Sorry Kapusta, I was quick reading since I am at work, thought it was Dave cause I saw his name when I opened the thread. Appreciate all the info and answers here.

    I was an idiot on my last trail runs where I was setting up my suspension and thought the FG was adjusted by activating the lockout and turning. Obviously realised immediately when my LSC was changed. So I left it till I got home where I set it with the allen key. My FG was fully clockwise so I have set it fully anti clockwise with the hope it will help small bump sensitivity. I still think I will pull it out this week since I need to improve BO and there are reports that it helps with this. I dont really need it in the Totem. I might be picking up a Pike for my hardtail and I fully understood when I had my last one, so thanks for the tips if I need to tweak my new one.

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    I just got a new bike today with a Reba SL Dual Air 29" fork with an external floodgate adjuster. It's got "Gate 2.5" etched on it. When I turn the floodgate knob clockwise with the fork in lockout it never reaches the end of its travel. It just rotates freely like it isn't doing anything. Is there something wrong with my fork? I haven't finished assembling my bike yet so I haven't been able to ride it...

    Thanks.

  43. #43
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    Quote Originally Posted by billips1002
    I just got a new bike today with a Reba SL Dual Air 29" fork with an external floodgate adjuster. It's got "Gate 2.5" etched on it. When I turn the floodgate knob clockwise with the fork in lockout it never reaches the end of its travel. It just rotates freely like it isn't doing anything. Is there something wrong with my fork? I haven't finished assembling my bike yet so I haven't been able to ride it...

    Thanks.
    Regardless of where the compression knob it set (locked or unlocked) the floodgate knob should have a defined range of motion. So it sounds like there is something wrong with your knob.

  44. #44
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    @billips1002
    You do not have an externally adjustable floodgate. You have an internally adjustable one. The golden knob is just a cap in this case. You take off this cap and adjust the floodgate with a 2.5 mm hex key (you can use the rebound adjuster knob for that).

  45. #45
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    Quote Originally Posted by Seb71
    @billips1002
    You do not have an externally adjustable floodgate. You have an internally adjustable one. The golden knob is just a cap in this case. You take off this cap and adjust the floodgate with a 2.5 mm hex key (you can use the rebound adjuster knob for that).
    Yes, you are correct. I finally realized that when I took another look at my bike just after making that post. I guess I shouldn't be working on my bike so late. But I couldn't help myself with the excitement of getting a new bike.

  46. #46
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    Quote Originally Posted by Seb71
    @billips1002
    You do not have an externally adjustable floodgate. You have an internally adjustable one. The golden knob is just a cap in this case. You take off this cap and adjust the floodgate with a 2.5 mm hex key (you can use the rebound adjuster knob for that).
    Wow, I feel really stupid for not putting that together

  47. #47
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    Quote Originally Posted by kapusta
    Wow, I feel really stupid for not putting that together
    Imagine how I feel for posting such a dumb question...

    Now I need to get my bike put together and start tuning my fork. My bike is a 29er hardtail. Is there any consensus on setting positive vs negative pressure in a dual air? I'm a fairly heavy guy. I weigh around 230 pounds. I was thinking I'd start the positive pressure at 150 psi (per the users manual) and start tuning with the negative pressure near the same.

    I noticed that the Reba users manual says to set negative pressure slightly greater (but no more than +15psi) than the positive pressure. But I saw many forum members prefer lower pressure in the negative chamber compared to the positive chamber. Which is most likely to be the "right" way?

    Also, the users manual says that a person my size should adjust the floodgate 0-0.5 turns from maximum floodgate (full clockwise). Does that sound about right as a starting point for tuning?

  48. #48
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    I'd tune your fork as follows:
    - back off rebound and comp fully, back the floodgate right off
    - start with no pressure in the neg air
    - adjust pressure in the positive air until you get the amount of sag you want (or perhaps 5mm less than you want).
    - pressure up the neg air little by little until you like the feel of the initial travel (this may give you more sag as you increase the neg air pressure)
    - find some a series of short sharp bumps to set your rebound - ride the same bumps and keep dialing in rebound until the fork starts to pack over the bumps (eg. rebound too slow) and then back off the rebound a few clicks
    - find a slight uphill climb and set to full comp, with floodgate backed right off - get out of the saddle and hammer the climb, keep adding in (+) floodgate clicks until the front end bob of mashing out of the saddle is under control.

    Enjoy!

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